Heckler & Koch HK23
- Category
- Machine Gun
- Barrel
- 450 mm
- Weight, empty
- 8.50 kg
- Introduced
- 1972
About
What it is, and why it matters
The Heckler & Koch HK23 is a German 5.56x45mm NATO light machine gun derived from the 7.62mm HK21 and based on the G3 / HK33 roller-delayed blowback system. Introduced in the early 1970s, it fires from a closed bolt at about 750 rounds per minute and feeds primarily from a belt, with a conversion kit allowing STANAG box-magazine feed. The modernized HK23E was offered as the XM262 in the US squad-automatic-weapon competition of the early 1980s, where it lost to the FN Minimi (M249).
H&K entered the HK23E into the US Army's automatic-rifle trials as the XM262, hoping to scale up the G3's roller-delayed family into a SAW - but the belt-fed Belgian FN Minimi won and became the M249, leaving the HK23 a 'SAW that could have been'.
The magazine-fed automatic-rifle counterpart is the HK13. The 'E' (Export) variants belong to the 1980s modular HK11E/HK13E/HK21E/HK23E family that share a common receiver, trigger group, and interchangeable barrels and feed units.
Specification
Everything measured
IdentityWhat it is, who built it and when.
- Manufacturer
- Heckler & Koch
- Category
- Machine Gun
- Country
- Germany
- Status
- In service
- Produced
- 1972
DimensionsAs issued, without a magazine or an optic.
- Barrel
- 450 mm
- Overall length
- 1030 mm
- Weight, empty
- 8.50 kg
ActionHow it cycles, what trips it, and what feeds it.
- Action
- Roller delayed blowback
- Firing mechanism
- Hammer fired
- Trigger
- Single stage
- Magazine
- Belt
MaterialsEach swatch is the material itself, not a colour chosen to stand for it.
- Frame
- Steel
- Barrel
- Steel
- Stock
- Polymer
- Finish
- Phosphate
BallisticsFrom the service cartridge, not a handload.
- Muzzle velocity
- 910 m/s
- Muzzle energy
- 1664 J
- Effective range
- 1000 m
- Maximum range
- 2800 m
- Rate of fire
- 750 rpm
Trajectory
What the round does downrange
Solved from the muzzle figures and the bullet. The dashed rule is the effective range on the record, and the crosses are the steps the solver returned.
Features
What it has
What the record lists as fitted, drawn from the catalogue.
Quick change barrel
Closed bolt operation- Interchangeable feed unit
Bipod- Tripod mountable
Convertible belt or magazine feed
Standing
How it compares
Each figure against the firearms of the same type and cartridge that record it, or of the same type where that cartridge has too few. Positions are read to the nearest tenth.
| Measurement | This firearm | Median | Position |
|---|---|---|---|
| Empty weightAmong 27 5.56x45mm NATO machine guns | 8.50 kg | 6.35 kg | Among the heaviest tenth |
| Overall lengthAmong 25 5.56x45mm NATO machine guns | 1030 mm | 1020 mm | Longer than about 70% |
| Barrel lengthAmong 26 5.56x45mm NATO machine guns | 450 mm | 465 mm | Shorter than about 60% |
Answers
Questions about the Heckler & Koch HK23
How much does the Heckler & Koch HK23 weigh?
The Heckler & Koch HK23 weighs 8.50 kg (18.74 lb) empty.
What caliber is the Heckler & Koch HK23?
The Heckler & Koch HK23 is chambered in 5.56x45mm NATO.
How long is the Heckler & Koch HK23?
The Heckler & Koch HK23 is 1030 mm (40.6 in) long overall, with a 450 mm (17.7 in) barrel.
Who makes the Heckler & Koch HK23?
The Heckler & Koch HK23 is made by Heckler & Koch (Germany).
When was the Heckler & Koch HK23 introduced?
The Heckler & Koch HK23 was introduced in 1972.
How does the Heckler & Koch HK23 operate?
The Heckler & Koch HK23 uses a roller delayed blowback action, and its firing mechanism is hammer fired.
Compatibility
Which parts fit this firearm
Studio
Every part that mounts on this, resolved
Not a list the maker typed out: the answer comes from the mounts this firearm exposes and the interface each part needs, so it stays right when either one changes.
- Every part that mounts on any firearm in the catalogue
- Interface standards, platforms and fit overrides
- The same answers through the API and the MCP server
Requires a signed-in GunSpec account on the Studio plan. The answer is computed per part, so it is not part of the public record.
Provenance
What the record holds
Every figure above was taken from one of these pages. The confidence reflects how much of the record came from a page a claim can be checked against.
In service
- Turkish Gendarmerie
- Türkiye
- United Arab Emirates Armed Forces
- United Arab Emirates
Provenance
Confidence in this record
72%
Stockists
Where to buy
Offers link straight to the shop. GunSpec never takes the order.
No shop has listed this firearm yet
Stock and prices come from the shops themselves. If you sell this firearm, you can list it and it appears here.
List a firearmMCP
Ask an assistant about it
The same record, reached the way a person asks for it rather than the way a program does.
Ask GunSpec
Works with
Point an MCP client at GunSpec and it answers from the catalogue rather than from memory. A free key covers the read tools.
API
The call that returns this record
The same fields, in the same units, from the same endpoint the page reads.
curl --request GET \ --url 'https://api.gunspec.io/v1/firearms/hk23' \ --header 'X-API-Key: your_key'{ "id": "hk23", "name": "Heckler & Koch HK23", "manufacturer": { "id": "heckler-koch", "name": "Heckler & Koch", "countryCode": "DE", "foundedYear": 1949, "website": "https://www.heckler-koch.com", "logoUrl": null, "description": null, "status": null, "defunctYear": null, "stateOwned": null, "makesFirearms": null, "parentId": null, "predecessorId": null, "createdAt": "2026-04-05 22:24:37", "updatedAt": "2026-04-05 22:24:37", "version": "ae60994f5b45d604da21fcd14b728cfa9d2e62000c92e596de4c48c4be768979" }, "category": { "id": "machine-gun", "name": "Machine Gun", "description": "Fully automatic firearms for sustained fire" }, "country_of_origin": "DE", "year_introduced": 1972, "barrel_length_mm": 450, "weight_empty_g": 8500, "action_type": "roller_delayed_blowback"}